Continuous inductive train control system



1929 6 SheetsSheet 1 Sept.`22, 1931. w. D. HAILES CONTINUOUS TNDUOTIVE TRAIN CONTROL SYSTEM Filed July 2o.

TORNEY Sept9 22, 1931. w. D. HAILES CONTINUOUS INDUCTIVE TRAIN CONTROL SYSTEM s sheets-sheet 2 Filed July 20. 1929 nim tuch Wunm.

lNvE 0R ,/ATTOR'NEY Sept, 22, 1931.

w. D. HAlLx-:s 1,824,134

CONTINUOUS INDUCTlVE TRAIN CONTROL SYSTEM F'iled July 20, 1929 FIG. 3. wel

Control on C'urr'erl'l Off m WVU-Lr Quick. 121 .j

6 Sheets-Sheet 3 With Fiel decoder, Frequency code af .1 secvievmsterthan release time C25ec)o`f` executing relay Pfall relays 'P1-:E6 pick up, no execution is possible and cab .signal is 72 on lecs-*lp c Current I OPF Quick T21 f Executes '/1 Hump Code assec. 123

.sa sec. 125

With Fis. 1 decoder, frequency code ofsecs., ie., slow enough to allow execution and clearout, by

dropping QiandPB--Prespectvelw fup nothing more W35/ than a, one-hump code an be executed, and relya b4/@ P-725only, can be picked up. BY '/AT u TORNEY Sept. 22, 1931. w, Dv HAILES 1,824,134

CONTINUOUS INDUCTIVE TRAIN CONTROL Sx'LEM Filed JulyY 2O 1929 6 Sheets-Sheet 4 o" I I I I I I I IIII IIIIIIIIIIII ."";.II lI,IIII|IIIl Qufck cpp VII-1 7, I I l i I i I-I-I-L I I I I I I I I I I I I I I I I I I I u l I I I l l I l I I l l 1 l l i Q 'ck Q I.f I I I I IExsIfIcutgeslHurlppclpde!l I I I I I' I I I .Zaunz I I I I i I 4 I I l i I I I I| i i I Il I, I I IL.. I f .asse .12s I I I |III|I|I|IIII|I I I I I I I I I I .ecl I I I-I I I I I I I I I I I I I I I I I I I I I I I I I assemzsI I I I I I I I I I I I I I I I I I I .55592126 I I I I I I I I I I I I I I I I I I I I With Fia! deoder, a. frequency code of .4 Sec, ie., slow enough to drop executing relay E? but not slow enaugh to drop relays-Tto clear outJ monitor relay Eidrops at .second pick-up oIfCPR to enFQf-ce a, amr-out 5o ndt anIy DI-125cm be picked up n.5 in Fa.4,to execute only@ one-hump code FIG. IERI Sept. 22, 1931. w. D. HAILEs CONTINUOUS INDUCTIVE TRAIN CONTROL SYSTEM e sheets-sheet '5 Filed July 20, 1929 NormaJ Operation of Decoder I I I :mw

I I I II II 4.5 n.2 .c, am. m5

IIIII ATTORNEY Sept, 22 1931.

w. p. HAILES CONTINUOUS INDUC'IIIVE TRAIN CONTROL SYSTEM Eiled July 20, 1929 mi FIG. 1l.

6 Sheets-Sheet 6 I Cpl I I I I I I I I with Fa.7decoder;a. frequnuy :ode daeca, e.,slnw enough @i I I I I I I I t drop executing rainy 'Rf but p2 m LI P5 *I ndt .slow cnaugh to drap releyg Eg-Pf# lapin clean eut 'Pialready dawn an snond pick up Gm-- Fie. 10.

GPQ With Fia.7'def.r..-:lerJ a, frequency code oisecs., ie., .slew enough to 721 I I I allow execution and clear-out by 2 droppngand psapecfivcly, Q fifup, nothing more than a.

of CP1?, Co enfarce n. clearout au 'Chet only Plandzcdn be picked up, as in FiaJO, to execute nnly a one-hump code.

one-hump code een be executing. and re lays 'Piand'z only, can be picked up.

With F157 decoder, Frequency code of .2 seconds, ieJ no?, slowerthen releaee time Csec) ofexecutng relay 12,1 n.1 l relays 122- -Pspick up, no execution is possible and cab R4 Fx signal i512.

Fae.. 1E .2 .Se @PR *I *ha am With Fls.7decoder; @asume fat Rate as Fm has been bicked up Q1 f f and then Changes to Ls/awel' rete as F1611, Execute one G impulse than no Further executions other 3 then acne-hump code can go overand n One impuls 0f "G1/can not break p4 FR* down the 72ed that was setup 5 by the fast rate 1? MF1 oRNEY WILLIAM D.. HAILES,

Patented Sept. 22, 1931 UNITED STAT ES OFFICE SIGNAL COMPANY', OF BOCHESTER NEW YORK CONTINUOUS INDUCTIV'E TRAIN" CONTROL SYSTEM Application 1ed- Inly 20; 1929*. Seri-a1- No'. 379,638.

cation. i This inventionI solvesk the same generali problem, with regardY to cyclic or countmg type code sy-stemsasfissolved by alpplicants late,r1tV 1,79%',@09y granted March 3, 1931, in

connection Wlth' systems responsive to rate ,l or frequency type codes;

The present invention isf primarily an iin" provement in decoding: means for use incon'` nection with sys-tems such, as shown for exe ample, in the-VV. D. Hailes application Ser. No. 228 ,059filed October 22', 1927, and rela-ting to alternating` current train control systems-, and as shown in the Hailes application SerNe. 249,457 iled January 25, 1928 and relating to direct current train control type of systems.Y

In the same manner in which one is much less likely to encounter' accidentally produced codedA train control current than tol encounter accidentally produced uncoded train cont-rol current, it is quite apparent that one is less likely to` encounter accidentally produced codedtrain control current ofthe counting or pattern type than to encounter accidentally produced coded train control current of the frequencyJ or non-patterntype.

In the applications above referred tothe systems disclosed are' designedv to distinctively; respond'to coded train control current ofE the: cyclic orv countngcode type as distinguished fromk the` frequencyfcode type', placed on the' track rails. It is possible however t'o'- pro-- duce a code of' the frequency' type which will operate these systems to set upa proceed indication in the engine calo. It is thus'seen thatv under danger or stop conditions, in which either no train control current', orA a steady uninterrupted trains control current, is norinally4 present 1n the. track rails,.1t 1s conceivable thaty a vibrating? Contact or loose. Wire,

` or the like on the trackway ory on thelocomotive, might operate to accidentally produce a: frequency type code; so as to operate the4 decoder of theI systems in questionzto Setup. az proceed:` cab indicationt. Y

With the forms of decoders shown im the applications 228,059, and 2494,45@ above referred to, @for example Fig. 62 of applicare tion 228,059) the decoding means includes; relay-s for selectivelyr` setting up; circuitsfv for the different cab indications, means: for'theni placing; energy on the particular circuit', just set up, and means tor then restoringv the de coder' tov normal condi-tion and breaking that circuitset up; for` eaclr cycle of'code.

In other-Words,l a cyclic code: operates to: first set up a circuit for controlling a cab; indication, a means for their energizing this circuit, andameans operaloley subsequentf ly thereto for breaking this circu-itgthe last; two means being relaysiandz conveniently lie-- ingf considered as exccuting'and clean-out rc;-y laysf respectively;

It is clear that with a, frequency typo code? with: a gieren timing of on and oil periodszo current whichl is insuicient. to afl-low theiexez outing relay to release,x no proceed control: circuit Whichi this code can alternately cani executed orl energized', andiV hence in accordance with` the systemin' questione, sr. stop indication. results. In this: easev the fre-l quen'cy codeis'incaipahle oi lgiyinga favorable: indication;

Again, with; afireqnency' type code witlr a', given tinn'ng oni and` oi periods` oi current. which time is' suiiicientl not only tor allow' time executing relay to release but also to permit clearingY out of' the decoderafter such release, only the control circuit corresponding toa .one-hump codel can. be: seti. up and'. exe-- OF ROCHESTER NEW YORK, ASSIGNOR TO, GENERAL RAILWAY' .In this manner it is possible for the decoding means of said two cases to respond to a frequency type code to successively set up more and more favorable indication circuits and to execute each in turn, thus to finally set up a proceed indication circuit which thereafter' is maintained and periodically executed.

One purpose of the present invention is to provide a decoding` means for counting or cyclic type codes which cannot respond to a frequency type code, regardless of the timing of such code, to set up favorable indications. This is accomplished by providing either a special supervisory or monitor relay for preventing such response to a frequency type code or it is accomplished by arranging the various counting relays constituting the decoder so as to give a monitor control and prevent such response to frequency type codes. V

In the present invention, the functions of execution and clearing-ont are combined in a single relay, .instead of having them separately handled by two separate relays as in y the said two applications.

It is further provided, in the present invention, that due either to the monitor relay, or to the particular arrangement of counting relays, execution cannot occur without clearing out also occurring immediately there- In this manner, as with the two Hailes applications 228,059 and 249,457, a frequency type code which is too fast to permit execution can only result in setting up a stop indication while a frequency type code which is slow enough to permit not only execution but clearing out, cannot pick up the decoding relays beyond those required forrsetting up the one-hump code circuit and hence can only result in intermittently setting Iup and executing a one-hump code circuit.

In other words a fast frequency code can pick up all the relays of the decoder but cannot execute any circuit, so that a stop indication is set up, while a slow frequency code, on the first off period of current, executes to execute a one-hump code indication if employed, and if the olf period of current be long enough a clearing out of the decoder follows.

If, however, in the present invention, the period during which current is off is only long enough to execute, but not long enough to clear out in the normal manner, the next on period of current causes the monitor relay or control means to release and enforce clear-out of the decoder'. Thus, regardless of the rate of the frequency type code, any execution must be followed by a clearingout of the decoder so that the frequency'code cannot operate through the decoder beyond the`point for completing a one-hump code circuit.

In view of the above considerations, as

will more clearly appear after the detailed description of the invention which is to follow, reference being made to the accompanying drawings, it is contemplated by this invention to use, if desired, but three indications, instead of four indications such as employed in the Hailes application 228,059 above referred to, with the caution or Y indication, corresponding to a one-hump cyclic code, entirely omitted. In this manner, by omitting the one-hump code indication, the decoder is made wholly non-responsive to frequency type codes for setting up anything but a stop indication.

If, however, it is desired to use four indications, it is contemplated by this invention to still omit the one-hump code indication and to supply an added indication by employing two additional counting relays (as ,RT and R8) whereby to add to a thoroughly safeguarded system having three indications as considered just above, a fourth indication. This four indication system then would include indications in addition to the stop indication, corresponding to two, three and four hump codes for setting up in the cab, respectively, Y, Y/G, and G signals.

In the above manner, thisv invention contemplates a system having decoding means capable of giving any desired number of distinctive indications, and at the same time be wholly non-responsive to frequency type codes to set up any but a stop indication. n

It is` further contemplated to. provide means for checking the operativeness of the monitor relay, whereby to indicate when the system is not protected against response to frequency type codes by the monitor control.

Further objects, purposes and characteristic features of the invention will appear as the description progresses, reference being made to the accompanying drawings showing, solely by way of example, and in no manner whatsoever in a limiting sense, several forms which the invention can assume. In the drawings Fig. lis a diagrammatic view of carcarried apparatus in accordance with one form of this invention, in which a warning whistle is included, but in which no brake applying means is employed, the apparatus including a check whistle or check red light), which sounds or lights up once for each cycle of code in case the monitor relay improperly sticks up.

Fig. 2 is a diagrammatic View of counting or cyclic codes useable in connection with the apparatus of Fig. l, and also shows the operation ofthe Fig. l apparatus by the respective codes.

Figs. 3, 4 and 5 are time studies, in graphic form, of the effects on the apparatus of Fig. l of fast, slow, and medium rate frequency codes, respectively.

' Fig. 6? is. a diagrammaticvie-w of' a slightly modiliedY form of the car-carried apparatus of Fig. l, in which. the whistle is` omitted` but brake applying apparatus is 1ncl'uded, and whereina control isincluded for giving an absolute stop regardless of aclmowledgment.

F ig; 7 is av diagrammatic View of another: embodiment ot the invention, and shows4 carc-arried apparatus. in which no vmonitor relay, per se, is employed, but in which decodingrelaysareso. connected up asto. give monitor control..

Fi'grSi is a graphic time study o the norn'i-al operation of thea-pparatus of Fig, 7 by pattern or cyclic type codes.

Fig-s. 9,10, and l1 are graphic time studies, respectively, of the response of thev Fior. 7 apparatus, to fast, slow, andi medium frequency or rate codes..

Fig. 12 is a graphic timel study of the response of the Fig. 7 apparatus to a fastchanging-toeslow frequency or rate code.

Referring now to the drawings, there is shown in Fig. l, a stretch of railway track constituted by rails 1, to which is. applied, and from which isY removed, train control current, either alternating or direct, in accordanceA with the variouscodesl used in connecgtion .with the car-carried! apparatus. For

example, the codes can bek as shown in Fig. 2, wherein it is graphically represented that current is applied for a short period ottime to the track rails, and is then removed theretrom for a short period of time, to be aga-in applied and again removed, etc., until one complete cycle of codes has been sent, after which the current is kept` offv ofv the rails for a selectively long time before another cycle off code is4 sent.

In Fig. 2 are shown codes wherein the proceed, or- G, code is. constituted by three suc- (lessive on and ott peri-ods followed .by an extended od period toA thus constitute a threehump code. For the approach restricting indication, Y/G, there is a two-hump code while for the caution or Y code there is a ene-hump code.l Thetiming of the codes is chosen'to properly cooperate with the car-carried apparatus and ofcourse this timing of the codes and; also of various parts of the car-carried apparatus can be, varied at will withoutl departing from the present invention. Y

Carriedon a Qanrepresented by wheels and Y axles 2, are receiving coils 8 in inductive relation to the track rails', whereby to receive energy i-nductively from the train control currents'. and pass` this energy through a filter F designed` to pass only the desired frerpuencyI oat? current if alternating current be employed.. The filter is connected to an amplifier A, the output side of' which is connected to. a coding primary' relayV CPR having contact ngers d and 5'. `The apparatus justdescribed is substantially identical with thecorresponding parts of the Hailesapplications 228,059 and 249,457.

- It will be seen from the above that relay CPR operates its Contact fingers 4L and 5 to: attracted and retracted position according as train control current is on, or oli, the track rails.

Control-led by the coding primary relay CPR is a bank of decoding relays R1, R2, R3, R4, R5 and RG which are connected up to pick up and to stay up in certain arrangements so as to place energy on the particular one of a repeater relay group constituted by relays. R Reg), Y Rep, Y/G Rep., and G Rep, which corresponds to the particular code being received.. The R Rep relay corresponds to stop conditions and is energized when none of theA codes ot Fig. 2 are being received by coils 3, under which conditions reiay CPR is maintained either in attracted or retracted position, so that ille stop indication is given when train control current is either steady on or steady oli.

Depending on which one of the repeater group of' relays is energized, a particular one of the wires g, l1//g, y/ or ris energized. For example, with relay R Bep, energized energy is applied to wire r.

Included in the invention is a group oi acknowledging relays l Stic, Y Sit/7J, and Y/G Stk, which, together with an acknowledgingcontacter noie arranged to silence an audible signal All/i7 i7, in the form oi a whistle valve which sounds when de-energized, the circuits being arranged so that any change to a more restrictive condition causes de-energization of the whistle AWV which continues to sound until the acknowledging contactor. is operated.

There is also included in the invention a visual cab signal for indicating the diderent traiiic conditions, by showing G, Y/G, Y, or l, corresponding respectively to proceed, approach restrictive, approach and stop, and these cab signals are controlled by various contacts of the acknowledging group of relays and of the repeater group of relays.

lith the exception of the decoding means constituted primarily by relays Rl-R* and an associated audibler check signal AlVVl which is a whistle which sounds when energized, all of the parts above described in connection with Fig. l, are substantially as set forth in the previously mentioned Hailes application 228,059 and 249,457. hccordingly only a further very brief description of the operation of this part of the apparatus is deemed necessary in the present application.

The apparatus of F l is shown in the condition and posit-ion assumed when the car is in a danger or stop block. Under these conditions, rela-y CPR is down and all ci the relays Rl--RG 'of the decoding group or" relays, are down, whereby to. break the energizing circuit for all of the repeater relays except relay R Rep, which is energized through a circuit including Contact linger 6 andback point of Y Rep, contact linger 7 and back point of Y/G Rep and Contact finger 8 and back point of vG- Rep. Energization of this R Rep relay places energy on wire r to hold relay R St c in energized position through a stick circuit which includes contact linger 9 and front point of R Rep, wire 1", contact finger 10 and front point of R Si c, and the winding of R Stk, (it being,

understood that acknowledgment has been perfo-rmed to iirst pick up relay R Stk, as is clear from the other l-lailes applications).

lith relay R Stic in picked up Condition relay Y Stk, is held vpicked up through its pick-up circuit which includes a front point of R S1575 and likewise relay Y/CT S570 is held up through a front point of Y With Y/Grltc in attracted position energy is applied to the acknowledging whistle MVV through a circuit which inc-luces Contact linger 11 and front point of Y/G Stk, acknowledging contact linger 12 and front point thereof, and the whistle in question.

Also with the conditions outlined above the R cab signal is energized through a circuit which includes the R signal, contact linger 13 and front point of relay l) Rep, wire 14 and contact linger 15 and front point of relay R S75/c.

On a change in traliic conditions as, for example, to clear, in which the G, or threehump, code of Fig..2 is placed on the track rails and picked up by the receiving coils 3, relay CPR picks up and releases in a ina-nner to follow the code and thereby operate the decoding relays R-RG in a manner to he more specifically described below. to pick them all up and hold them up, Y.vhereby to place energy on relay G Rep to pick such relay up so as to put energy on wire g through contact Vfinger 15 and front point of relay G Rep. Y

After expiration of the release time for relay R Rep, this relav drops to thereby deenergize its corresponding stick relay R Stk which in turn drops the other twostick relays of the acknowledging group whereby to take energy off of the whistle AWTV. But with t e G- Rep relay up energy is placed on the g wire to thereby energize the whistle A`WV through acknowledging contact finger 12 and front point thereof to thus preventV any sounding of the whistle on a change to more favorable traliic conditions. Thus, it will he observed, no acknowledgment is necessary when the change is to more favorable traflic. conditions. Likewise, the G cab signal is energied througha circuit .including a cont-act linger and front point of the Re?? relay and a contact linger and back point of each of the three acknowledging relays.

lf there now be a change in traliic conditions to less favorable conditions such, for example, as from proceed, or G, to approach restricted, or Y/G, the Y/G Code, the twohump code, operates CPR to cause the decoding group Rl--RG to remove energy from rclay G Rep and place it on relay Y/G Rep. As a result of relay G Rep releasing, energy is removed from the whistle AVV, and the whistle sounds and continues to sound until the acknowledging contactor A070 is de-A pressed.

This act results in picking up the R Stic relay through a. circuit including the normally open acknowledge contact finger 17 and back point thereof. With relay R Stk momentarily up, .relay Y S25/c picks up through a front point of R Stk, i. e. its next inferior relay, and in like manner an-d in sequence Y/G Stk picks up though a front point of its neXt inferior stick relay, and this last relay, after picking up, sticks up through wire lQ//g which is now energized due to the Y/G Rep relay being picked up, whereby to apply energy to whistle YWV through contact finger 11 and front point of Y/ G Stic relay, etc., whereby to silence the whistle. At the same time, the visual signal Y/G in t-he cab is energized through a front point of its corresponding repeater relay, Y/G Rep, a front point of the acknowledging relay .Y/(Jr Stcand a back point of each of the other two acknowledging relays.

` Thus, on a change to less favorable conditions, whistle AVV is sounded, and continues to sound until acknowledgment is performed.

The above described operation is substantially the same as occurs in the Hailes application 228,059 above referred to, to which reference should be made for a more detailed y description.

Coming now to the arrangement and operation of the decoding group of relays Rl-RG, for setting up energizing circuits for the various repeater relays R Rep, etc.,'it will be noted that relay R1, which is conveniently termed a monitor relay, is energized through a pick up circuit including a contact finger 171 and back point of RG, contact linger 18 and back point of relay R5, contact finger 19 and back point of relay R4, contact finger 20 and back point of relay R3 and Contact finger 21 and front point of relay R2, whereby relay R1 cannot pick up until after relay R2 is up and only then provide-d relays RS-R are down.

lVhen once `picked up, relay R1 can be stuck up through a stick circuit including contact linger 22 and front point of relay R1, and contact Enger 4 and back point of relay CPR, and also through a stick circuit including contact linger 22 and front point of R1, and contact linger 23 and front point of R2.

Before proceeding further in the description it should be noted that the` relays are i rails l.

variously timed as indicated in the figures of drawings, from which it is seen that relay R1 is quick to pick up and quick to release, while relays. Y .2- G are all quick to pick up, but are slow to release, R2 having a release time of approximately .2 seconds, while relays .R3-.RG- inclusive have release times of approximately .33 seconds.

As will appear more clearly as the discripf tio-n progresses, relays lits-RG each has a. pick-up circuit anda `stick-up circuit, the pick-up circuit of each relay including a front point of either R1 or R2 and a front point of all other relays of lower exponent value, (that is, of the relays to the left as view-ed in Fig. 1,) together with a back point of the relay having the next higher exponent value, (that is, of the relay nexttol the right as viewed in Fig. l.)

Furth-erore, the stick circuit for each of the relays lRit-.RG includes a front point of relay R1, R2, of the relay in question, and any other relay to the left thereof as viewed in Fig. l, together with a back point of the relay, if any, immediately to the right thereof.

Also included in connection with the decoder of this invention, is the above .mentioned Whistle AlVVl, which has `an energizing circuit including a cont-act finger 24 and back point of relay R2, a Contact finger 25 and front point of relay R1,and contact finger 5. and J:iront point of' relay CPR, whereby to operate, as described more fully below, to sound once for each cycle of code, in the event the monitor relay R1 improperly stays in attracted position. This furnishes a check on the functionin of' monitor relay R1 which, if functioning properly prevents response of the decoder to frequency `type codes to set up anything but stop indication. y

Considering now the operation of the de-v coder, assume that a one-hump code, such as shown in Fig. 2, for Y, be applied to the track Relay CPR picks up 'once and releases once for each c ycle of code. On the first pick up of relay CPR, relay R2 is energized through contact finger t and front point of' relay CPR, through a circuit which is obvious from theV drawing. Immediately on picking up of relay R2, its contact linger 2l and front point completes the aboveretcrred to pick up circuit for relay Rc1, whereu pon relay R1 picks up, and being picked up,

' sticks up as referred to above through contact linger 23 and front point of relay R2.

On the first release of relay CPR, relays R1 and B3 being up, relay R3 is picked up through a circuit including Contact finger 5 and back point oi CPR, contact finger 2 6 and front point or" relay R2, and contact finger 27 .and hackpoint ofy relay R4; 1

Thus the ene-hump code operates to pick up relays R11-R3 which operate, on the sub- .Sequent-A release cf relay R2, two-tenths secv onds after its de=energization, to complete an energizing circuit for t-he repeater relay Y Rep, corresponding to the Y code, which circuit includes contact finger 23 and back point of R2, Contact finger 28 and front point of R1, Contact finger 29 and front point of and contact finger 30. and back point of R4.

If, instead of the one-hump, or Y, code, av two-hump or Y/ G code is received, on the sec.- ond successive pick-up of relay CPR, relay lit is'picked up. through a circuit including the contact lingers. 5. and 25 and their front points, contact finger 3l and front. point of R3, and Contact finger 32 and back point'of R5. Once up, relay Rt is stuck up through a stick circuit which includes contact fingers 37, 36, 311v and 271 and front points of relays R1, R2, R3 and R4, and contact finger 33. and back point of R5.

On the second release of relay CPR, relayv R5 is picked upy through contact linger 5 and back point of relay CPR, etc. in a manner similar to that described in connection with the pick up of relay R3, and when once picked up, relay ris stuck up in a manner Similar 'to that described in connection with relay Bft.

Thus with a two-hump. code, relays Rl-R are picked up, with R3-R5 stuck up, whereby, upon the subsequent release of relay R2, an energizing circuit is completed for Y repeater relay Y/Glep, which includescontact finger 23 and` back point of R2, contact finger 28 and, front point of R1, Contact linger 29 and front point of R3, contact, linger 30 and frontl point of R4, Contact finger 34 and front pointof Rtand contact finger 35, and back point of RGL VIn a similar manner, with a three-hump or G- code, as shown in Fig. 2, the third successive pickfup of CPR picks up and sticks up R6, the third release of CPR having no operative effect, whereby,- with this code, energy is transferred lby contact -nger 35 and back point of relay R6, from the Y/G Rep relay to the G Rep relay. n

i In Fig. 2, not only are the different codes graphically shown, but, also is shown the normal operation of the decoder relays 11i-#R6 in response to the, codes,

Considering the yGV code, for example, is seen that on the first pick-up of relay CPR, first relay R2 picks up, and immediately thereafter relay R1 picks up, and on thelst release of CPR, relay R3 picks up and Asticks up. On the second pick up of QPR, relay Rt picks up and sticks up, While on the second release of' GPR relay R5 picks up and sticks up.' On the third pick up of' CPR, relayRG picks up and sticks up whileon the third release of GPR nothing immediately occurs, but it is clear from Fig. l', that energy is re-v moved, by the release of' CPR, from relay R2 which can he conveniently considered the executing relay. y A

As shownl in `lj`ig.-2, with the. particular timing chosen, .2 of asecond after CPR releases, for the third time, relay R2 releases to thereby energize the Gr Rep relay.

. Release of executing relay R2 also breaks the stick-up circuit for relays Ra--R6 at contact finger 36 of relay R2, whereby .33 seconds after the release of relay R2, relays RS--RG release to clear out the decoder and prepare it for the next cycle of code, whatever that relay R2, is broken, the other stick circuit 'for relay R1 which passes through contact finger 4 and back point of relay CPR is intact so that relay R1 is maintained up.

On the first pick up, however, of relay CPR l. in the next cycle of code` the last referred to 25 stick circuit for relay R1 is broken by the picking up of contact finger 4 of CPR and shortly thereafter the other stick circuit for relay R1 is Vcompleted by R2 picking up itsv contact finger 23. During this intervening period however, during which both stick circuits for relay R1 are broken, relay R1 releases to thereby break the stick circuit for relays Ra-Re by releasing its contact finger 37.

As shown in Fig. 2, in connection with the G code, immediately after relay R2 picks up on the first impulse in a cycle of code, relay R1 immediately follows provided all of the relays Ra--R6 are at that time down, or, in other words, provided a clearing out .of the decoder Vhas taken place between successive cycles of code.

Thus it is seen that in the Anormal operation of the decoder of Fig. 1, at the beginning of each cycle of code monitor relay R1 first releases and then, after the picking up of relay R2, immediately picks up, since under the normal operation, there is a sufficient blank or oif period of current between successive cycles of code to not only permit relay R2 to release and thus apply energy to the particular repeater relay chosen, but also sufficient to permit relays R3--R6 to release.

We come now to the operation Of the decoder underrabnormal conditions, that is, for example, under conditions of frequency codes which may accidentally V-be present and against which it is necessary to be protected.

In Fig. 3, for example, there is shown a i frequency code, that isa Code having no particular pattern and including no extended off or blank periods. As indicated by the caption of the Figure, this code is fast enough, .l second, to be faster than the release time of executing relay R2 so that the first three impulses of code will successively pick up the various relays R1-R6 as described above. But inasmuch as there is an insuficient time during which current is removed from the track rails to permit relay R2 to release its contact fingers, no energy can be applied to the circuit which has been set up for repeater relay G Rep. Thus, with no execution, energy is on relay R Rep and stop conditions are set up, so that with this timing of freuency code the decoder is incapable. of re sponding thereto to give a favorable indica-` tion.

Referring now to Fig. 4, a frequency code is here shown having a different timing, namely, a timing in which the off periods or blanks are of suflicient duration not only to permit release of relay R2 and effect an execution, but also to release all of the relays RS-R6 which may have been picked up, to thus permit clearing out of the decoder.

-l/Vith such a code, relays R11- R3 are picked up on the first on and off, and then the circuit set up, which is for the repeater relay Y Rep, is executed by release of relay R2, after which relay R3 releases. Thus when the next impulse of code is received the decoder responds anew and merely repeats what has already been described. Hence this timing of code cannot progress through the decoder beyond the R3 relay. It is thus seen that the most that can be done with such a code is to cause the decoder to respond to execute a one-hump code and set up the indication corresponding to a one-hump code.

Thus,t0 discard the one-hump code is indicated, andby so doing the decoder is made wholly immune to respond to such codes for showing anything but a stop indication.

Coming now to Fig. 5, there is here shown a frequency code, as indicated by the caption, which falls between the two previously considered codes with regard to its timing. In this case the timing is such that execution is permitted by the blank or off period but it is of insufficient duration to permit the usual clearing out of the decoder by the dropping of such of the relays R3--RG as may have been picked up.

In this case, after the first on and off period, relays R1 3 are up, and on release of relay R2 to execute, energy is applied to the Y`Rep relay and one of the stick circuits for R1 is broken. On the next on period of current, relay CPR picks up as usual, and thereby breaks the only remaining stick circuit forvrelay R1, the monitor relay, which releases before its other stick circuit, through contact finger 23 and front point of relay R2, is completed by the subsequent picking up of relay R2. With the monitor relay R1 down, the stickcircuit holding R3 up is, and remains, broken, and hence after a proper lapse of time, depending on the release time Afor relay R3, such relay releases to thus clear Vso out the decoder, and it is only after the release of such of the relays .R3-R6 as are then up, that monitor relay R1 picksy up so as to permit the normal operation of the decoder.

Thus, in the case of a code such as that of Fig, 5, all that it can accomplish is to operate through the decoder up to picking up relay R3, the monitor relay then stepping in if, as in this last case, the blank period is not long enough to clear ont the decoder as is the case in Fie. 4, and enforces clearing out ofthe decoder. In this manner the code of Fig. 5 can do no more than repeatedly set up and execute a. one-hump code, and accordingly, as in connection With Fig. at, the discarding of any indication corresponding to a one-hump code is indicated and is contemplated by this invention.

By employing only codes of tvvo or more humps, the decoder of the form ot Fig. l is made Wholly immune against frequency codes to set up favorable indications. In the present instance, by discarding the one-hump code, the system becomes a three-indication system. having proceed, caution. and stop indicated, respectively, by G, Y and E cab iudications, and set up, respectivelj-f, in response to a three-hump code, a two-hump code, and current either steady on or steady oli'.

If a four, or more, indication system be desired, all that is necessary is to employ two additional counting relays as R7 and RS (not shown) foreach added indication, arranged in the same relative manner to the rest of the decoder as are present relays R5 and RG.. TWe should thenhave.v for example, a four-.indication system, including relays R11-RS, and responding to four, three and two hump .codes and current steady on or steady off, for setting` up cab indications of G, Y/G, Y, and E. This proc-ess can be applied to the decoder to give any number of indications desired.

Itis seen from the above ciscussion that the immunity of the decoder from favorably respondingto frequency codes, is depende` t on the proper functioning of the monitor relay R1. rFhis relay may improperly stick in either the attracted or retracted position.

lf relay R1 sticks in the retracted position, the executing circuit is permanently opened since it includes contact finger 2S of monitor relay R1, and With this executing circuit open, energy can only be applied to the R Rep relay of the repeater relay group, so that only a stop or R indication can be set up. Thus this failure is on the side of safety and is self-checking anoself-revealin If, on the other hand, relay R1 sticks in its .attracted position, so as not to release when' cle-energized, the protect-ion normally afforded by :this monitor relay is lost, and a frc- .quency code timed such as shown in Fig. 5, .can first pick up relays R1R3thcn execute mittent warning signal is sounded.

Y', and before clearing out is possible, can then on the next hiunp of code, pick up relays R4 and R5 to then execute Y/G", after which, before clearing out can occur, the next hump can pick up Re after which the indicati-on- G, or proceed, is periodically executed after each hump of code. In other Words, a code which, can cause execution, but is too fast to allow clearing out, can operate the decoder of Fig. l by successively picking up and executing the different indications, until it reaches the highest Or least restrictive indication, and then cancontinue to repeatedly execute this least restrictive indication, unless the monitor relay R1 be operative to enforce a clear? in g ont after eac-h execution, as explained in detail in connection With Fig. 5.

But with the arrangement shown in Fig. l, should monitor relay R1 improperly stick up, warning signal ATN V1, Which sounds When energized, will sound once for each cycle of cod-e so as to indicate thatA monitor relay protection is not present. The energizing circuit for Whistle ,Alvin passes through Contact linger 24 and back point of relay R2, contact finger 25 and front point of relay 'R1 and contact finger 5 and front point of relay CPR. r)Thus the Whistle is not energized when relay CFB is down and likewise is not energized when relay CPR is up, since, on CPR picking up, relay R1 releases before relay R2 picks up, and the release of relay RL breaks the ener.- gizing circuit just referred to for the signal. Thus, in normal operative condition of relay R1, signal ,ANVl is silent. If, however, relay R1 sticks up so that the decoder is deprived of monitor control, each time relay CPR picks up afterexecntion, the energizing circuit is completed for Whistle AVVl and remains energized for a short period until relay R2 picks up and breaks this circuit.

l From the foregoing it can be seen that the decoder, When subject to monitor control, is Wholly immune from frequency type codes for setting up favorable indications, and When not'subject to monitor control, if the defective operation of the monitor relay is such as to destroy this immunity from favorable operation by frequency codes, an inter- Of course, a visual or other type of signal can be used to replace either or both of the Whistles AVVVl and AWV.

Referring new to Fig. 6, there is here shown a fragmentary portion of car-carried-apparatus which constitutes a slight modification of the form shown in Fig. l. With this forni of apparatus, an added indication is obtained, whereby a rate type code of sufficient rapidity operates to enforce a stop control regardless of anything that the engineer can do.

In the form shown in 6, there is included an electro-magnetic device, EPV,

which can be of any usual or desired form,

and arranged to be normally energized and a ma when cle-energized to automatically apply the brakes. The energizing' circuit for the EPV includes a reset contacter Rcs and front point, and a Contact linger et() and front point of a control relay FFV-R, whereby release of relay EPV-B result-s in de-energization of the bralre applying device EPV. This relay EPV-R is provided with means, as by a copper band or the lille, for making it slow acting on release, so that it requires approximately live seconds release time, whereby deenergization thereof for short periods of time does not result in the relay releasing.

This control relay FFV-lienergized in much the same manner as is the whistle UVV in Fig. l, its energizing circuit including a Contact linger 39 and back point of relay R1, the acknowledging finger 121 and front point, and either the wire ll, or the wire 42 and contact linger 111 and front point of the Y/G Stk relay. Thus this contro-l relay is energized in a manner similar to the whistle fil/VV of Fig. 1, deriving its energy either directly through wire ll and the proceed repeater relay G- Regner, upon proper operation of the acknowledging cont-actor fic/c1, through a contact linger (111) and front point of the Y/G S1573 relay. The main dilference in Fig. 6, from Fig. l, is that the energizing circuit in question also includes the contact linger 39 and back point of relay R1 (the relay R1 'having an aditional contact linger 39 in the Fig. 6 form).

From the above described apparatus, it can be seen that, as in the Fig. l form, on changing to more favorable conditions, relay FFV-l?.- refnains energized without Vnecessity for acknowledgment, in the same manner as with UVV in l. On the other hand, when going to more restrictive conditions, energy is taken oli" of relay BFV-ld and is put en this relay again only if acknowledgment be performed within th release time, five seconds, of the relay. Acknowledgment after release of relay EPV-R is Vof noa-vail since the acknowledging cireuitin-cludes a contact linger 38 and front point of relay BPV- R Tf a 'knowledgment be not performed with-` in the re.l .ed time, on passing into mor restrictive territory, relay FFV4-Rreleases to thereby open the energizing circuit for the brake applying cevice FFV, with the result that an automatic brake application isincnrred. lt is then necessary, in order to release the brakes, and permit the train to proceed, to first bring the train to a full stop and then depress therreset contacter lies, which is accessible only from the ground, whereby vto place energy on wire 481 which operates in er to the Fig. 'l form to successively piel; up the inarious Ast-iclr acknowledging relays, to thus re-energize relay FFV- l wl ereby to re-energize FFV.

Coming newV to thefunction performed by contact finger 39 of relay R1, it is clear that unless this Contact linger be released at least once every live seconds, the energizing circuit for relay EPV- t is broken for asullicient time to drop this relay and cle-energize FFV, thereby to apply the brakes. Thus, by sending a frequency code having a timing fast enough to prevent release of relay R1 that is, fast enough to preventexecution, (see Fig. l) relay R1 which, as explained above is stuck up through a circuit including Contact linger 23 and front point of relay R2, remains up indelinitely, with the result that rela-y EPV-R drops and causes an automatic brake application. lt is obvious that Contact linger 39 can be transferred to relay R2 from R1 and obtain the same control of FFV-R.

While no whistle or other signal corresponding to AWVV of Fig. 1 is shown in Fig. G, it is clear that such a whistle can be employed, and connected up, in Fig. 6 in the same manner as in Fig. l so that, on going into more restrictive territory, an audible signal is given to indicate that aclnowlec gment is necessary. If acknowledgment be performed within the drop-away time of relay FFV-R, the acknowledging signal will be silenced and an automatic brake application will be forestalled. lf, however, acliio.vletlgiiient be not performed in due time, an automatic brake application results and the acknowledging whistle continues to sound until the reset contacter is operated.

lt is to be understood that all of the features of Fig. l are to be retained in the form shown in Fig. 6, this Fig. 6 showing merely the features additional to Fig. l, which features are constituted primarily by the absolute stop control in response to a relatively rapid frequency code, together with the brake applying means etc. In Fig. 6, therefore, there is shown a system which includes not only four cab indications in the same manner as in the form of Fig. l, but a lifth control which is an absolute stop control, produced by a relatively rapid frequency code and which cannot be forestalled by acknowledgment or any other act which the engineer can perform. Y

Referring now to Fig. 7, there is here shown a portion of car-carried apparatus constituting a simplified and improved decoder wherein the monitor control for guard- `ing against operation of the Vdecoder by frequency type codes for setting up favorable indications, is present, although one relay less, for a given number of indications, is employed in the decoder.

In this form of invention, as in the form of Fig. l, there are track rails 11, occupied 'by a ear indicated by wheels and axles 21,

carrying receiving coils 31, connected up through a lilter F1 and an amplilier A1 to a coding prima-ry relay CPR having contact fingers 41 and 51 whereby the contact lingers 4.1 and 51 pick up and release in accordance with coded current in the track rails 11,

Controlled by relay GPR is a decoder constituted primarily byl live decoding relays Rl-R.

Each ot the relays Ril- 1R5 has a pick-up winding and a stick-up winding, and is Varranged, as indicated on the drawings, to` be slow to release, relay R1 requiring .2 seconds to release, and each of the others requiring .33 seconds to release. l' l f In accordance with the particular code on the track rails, this decoder operates to place energy on the various wires y1 and g1 to energize, respectively, a caution repeater relay, and a proceed repeater relay, as in the form shown in F l. A wire 44 is indicated in dotted line in Fig. 7 to indicate that this wire which would be energized by a Onehunip code, is entirely discarded in order to make the decoder wholly immune from frequency or rate type codes, as explained above. Accordingly the `decoder of Fig. 7 is arranged to give three indications, a proceed or Gr indication by placing energy on the g1 Wire in response to a three-hump code, a caution or Y indication by placing energy on the y1 wire in response to a twohump code and a stop or Rindication in response to a one-hump code, and to current steady on or steady off. The red repeater relay, R Rep, of Fig. 1 is, in the form shown in Fig. 7, energized through a circuit includinga back point or each of the relays Y-Rep and CY-Rep whereby in the absence of either a proceed or a caution indication, a stop indication must necessarily be shown.

It it be desired to have the .decoder of Fig. 7 give four indications instead of three, it is preferable, instead of using the indication corresponding' to a one-hump code, to employ two additional decoding relays, as RG and R7, connected to the right of relay R5, in the same manner as to be described in detail below in connection with relays R4 and R5, whereby to give an indication controlled by a four-hump code. In this manner a decoder ycan be built up giving any desired number of indications and still be wholly immune from favorably responding to a frequency orrate type code.

Before giving a detailed description of.

the various circuits involved in the decoder of Fig. 7 it may makefor clearness to state that, with current steady on or steady off, all of he relays Rit-R5 are down. Vith a one-hump ,code only relays and R2 are picked up, rfor executing a one-hump code indication (which as just described has been wholly discarded). With `a two-hump lcode relays lil-R4 are picked up to place energy, upon execution, on the Q/l wire. Tith a three-hump code relays Rl- RS are picked up toplace energy, lupon execution, 011" .the g1 wire.

The: Voperation of the decoder will be dtraced in response to a three-hump pr proceed code such as shown, for example, in Fig. 8, and this will explain clearly the operation of the decoder in response to the twohuinp code and a one-hump code if any, it being remembered that the two-hump code stops at picking up relay R, while the onehump code stops at picking up relay R2..

On relay CPR picking up for the lirst time, relay Rl is picked up through a circuit including contact linger 41 and front point of CPR, contact finger 45 and back point of and the pick up winding PU of R1.

On the subsequent release of GPR, relay R2 is picked up through a circuit including contact finger 51 and back point of QPR, contact finger 46 and front point of R1, contact finger 47 and back point of R3 and the pick up winding PU of R2. After being picked up, R2 is stuck up through a c ircuit including Contact finger 48 and front point of R1, Contact linger 49 and front point of R2, the stick winding St/c of R2 and contact finger 50 and back point of R3.

On the second pick-up of CPR relay R3 is picked up through a circuit including contact inger 41 and front point of CPR, contact iinger 45 and front point of R2, contact `linger 5l and front pOillt of R1, the sti-ck windingV of R1, contact linger 52 and back point of Rt, and the pick up winding of R3. R3, after being picked up is stuck up through a circuit including the stick circuit traced above for R2, but with contact nger -5() of R3 in raised position, and Contact finger 53 and back point of R4.

On the following, or second, release of CPR, relay RL is picked up through a .circuit including the contact; fingers 51, 46 and 47 and front points of CPR, R1 and R3 respectively, contact linger 54 and back point of R5 and the pick-up winding of R4. Alf-` ter being picked up, relay R4 is stuck up in a l manner similar to what has valready been described.

On the third lay R5 is picked should new be pick-up of relay CPR, reup through a circuit which easily traceable en Fig. 7

vandeis stuck up through a stick'circuit which also should now be easily traceable.

On the third release of relay CPR, no further relays are picked up, but both the pickup and stick circuits for relay R1 are broken by the release of contact linger 41 of relay CPR, so that, in the present case .2 seconds after this' last release of CPR, relay R1 releases to break the stick circuit for the four relays R-y 5, kand at the saine time to complete an executing circuit for the particular code being received, in the present case the three-hump, .or proceed, code. This eX- ecuting circuit includes contact linger 48 and back point' of R1, contact linger 55 and front 'hump code, relays R1--R4 are picked up in sequence in the manner described above, but relay remains down, whereby to leave contact linger 58 of relay R5 down, thus to place energy on wire y1 instead of g1, to thus eX- ecute for the caution or two-hump code.

'Y The normal operation of the decoder shown in Fig. 7, and just described, is illustrated graphically in Fig. 8, with regard to both the G, or proceed, code and the Y, or caution, code. In this figure is shown graphically'how, after one cycle of code has pro- Vgressed through the decoding relays, the

dropping of relay CPR de-energiZes R1 which Acan be considered both an executing and a clear-out relay. On release of R1, contact 'finger 48 thereof drops to execute by placing energy on the proper repeater relay wire, and to break the stick circuitV for the remaining relays which have been picked up and are stuck up, so that these remaining relays subsequently release and clear out the decoder in preparation for the next cycle of code.

Referring now to Fig. 9, there is here shown in graphic form the response of the coderof Fig. 7 to a frequency or rate code which is equal to or faster than, the release time of the executing relay R1. As indicated in the figure, the first three humps of the rate code pick up relays R1-R5 but in as much as there is insufficient time during which CPR is down, for R1 to drop, no execution can follow. Therefore, no energy can be placed on either the y1 or g1 wire, with the result that the red repeater relay is energized to set up a stop indication.

Referring now to Fig. 10, there is here shown,'in graphic form, the response of the decoder of Fig. 7 to a frequency or rate type code which is slow enough not only to allow execution, by the dropping of relay R1, but also to allow the subsequent release of such ofrelays R2-R5 as have been picked up. As can be seen from the ligure, the first on and off period of current picks up relays R1 and R2, after which R1 drops to eX- ecute a one-hump code indication if it be used, but in the present case this indication has been discarded, and then relay R2 -releases to clear out the decoder. Thus it is seen that with a slow rate code, as illustrated,

vthe code can progress through the decoder only up to picking up of relay R2 and the time is sufhcient during the olf period of current to drop both of these relays so that each succeeding current impulse must start at the beginning of the decoder.

Referring now to Fig. l1, there is here shown in graphic form the manner in which the decoder of Fig. 7 responds to a frequency type'gcode which is "slow enough to permit execution by the release of R1, but is not slow enough to permit release of relays R52-R5 in the normal manner.

In this case, on the first pick-up of CPR, R1 picks up through a front point of CPR and a back point of R2. On the first release of CPR, R2 picks-up through a back point of CPR, a front point of R1 and a back point of R3 and is then stuck up as described above. Relay R1 then releases .2 seconds after the release of CPR to execute a one-hump code if used, that is, to attempt to place energy on such as the dotted wire 44 which, as explained, has been omitted. Before relay R2, however, has time to release, relay CPR picks up for the second time, but since the pick-up circuit for relay R3 includes contact finger 5l and front point of R1, R3 cannot be picked up, and also, since R2 is still up, R1 cannot be picked up, with the result that the second pick-up of relay CPR can have no effect until after relay R2 releases and thus clears out the decoder.

Thus it is seen that, with a rate type code such as in Fig. 1l,v the code cannot progress through the decoder beyond picking up relay t2, and it is also clear that, if any attempted execution occurs by the release of relay R1, it is necessary that clearing out of all of the other relays of the decoder which may have been picked up, be completed, before the code can further operate the decoder relays.

The form of decoder shown in Figure 7, therefore, accomplishes the same useful results as accomplished by the form shown in Fig. l, but is simpler and cheaper in that it eliminates one of the relays of Fig. l. That is, relays R1 and R2 of Fig. l are, in effect, replaced in Fig. 7 by the single relay R1.

It is to be understood, of course, that the check signal AVVV1 of Fig. l, and the acknowledging whistle AVV of Fig. l, and also .f

the brake control means EPV and FFV-R of Fig. 6, can all be used in connection with the decoder of Fig. 7. In other words it contemplated that the decoder (R1-R5) of Fig. y7 can be substituted .for the decoder A (R1-R6) of Fig. l.

Referring now to Fig. 12, it is here sho-wn in graphic form how the decoder of Fig. 7 is immune to a fast rate code which changes to a slow rate code as, for example, a rate code of .2 seconds changing to a rate code of sccends.

During the time'the fast rate code, .2 seconds, is being received, response of the decoder is as indicated in Fig. 9, in which all of the relays R1-R5 are picked up and are held up with no possibility of an execution since there is insufficient time for the release of executing relay R1.

On the code changing to a slower rate, as

irs

:3 seconds, relay R1 releases to execute the circuit then set up, which is thev proceed or G indication. VThus energy isplaced on Wire g1 on the first release of R1. Since execution has taken place, a. clearing out of all of the relays .R2-R5 is enforced inthe same manner as described in connection with Fig. 11, whereby, after this single execution ofv the G code, nothing further is possible except the attempted execution of a. one-hump code which it is contemplated to Wholly omit.

Furthermore a single execution of the G code cannot break down the stop Yor R code that was set up by the fast rate code since, as shown in F ig. l, the red repeater relay R Rep requires 6 seconds to release. Before this relay has-had a chance to release, the effect of the single execution of G code has beenk dissipated and G Rep releases, and again energizes R12-ep to thereby retain the stop or R indication. v y

. As mentioned in the introductory portions of this specification, the timings of the various relays and of the various codes not of th-e essence of the present invention, it being contemplated that these times can be Widely varied, at will, in accordance with the attendant circumstances, ust so long as the code timing is chosen to properly cooperate With therelafy timing to give operating characteristics as described. l

By means of the above described systems, applicant has provided train control systems vwhich are designed to vrespond normally to pattern or `cyclic or counting type codes, to

set up distinctive cab indications and train controls, with the apparatus so arranged as to be Wholly immune to operation by rate type codes, regardless of the particular iming of such rate codes, to set up anything rbut stop indications and stop controls.

The above rather detailed description of several forms of applicants invention, is given solely by Way o-f illustration, and is not intended, in any ina-nner whatsoever, in alimiting sense. Obviously, the invention can assume many physical forms, and is susceptible of numerous modiiications,`and all such forms and modifications are intended to be embraced bythis invention, as come Within the scope of the appendedclaims,

Having described my invention, I now claim:

l. In continuous train control systems, in combination With code receiving means and secondary circuits forfsetting up controlsof varying restrictiveness, a decoder for governing the secondary circuits and operated by the receiving means, said decoder having means making it incapable of setting up a favorable control in response to code `having spaced alternate on and olf periods of current, unless there intermittently occurs an off period, which is long relatively to said alternate olf periods.

2. In continuous train control systems, in combination With code receiving means and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and operated by the receiving means, said decoder being arranged to distinguish between cyclic codes diering from each other by the number of separate current impulses per cycle of code, and including means making it incapable of setting up a favorable control in response to code having spacedalternate on and off periods .of current, unless there intermittently occurs an olf period which is long relatively to said alternate olf periods.

' 3. In continuous train control systems, in combination With code receivingl means and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and operatedl by the receiving means, said decoder having means making it incapable of setting up a favorable cont-rol in response to vcode having spaced alternate on and oif periods of current, unless there intermittently occurs a relatively extended olf period, and out-oforder indicating means initiated upon said decoder failing to guard against responding favorably to a code having no intermittently occurring relatively extended olf period.

1l. In continuous train control systems, in combination With code vreceiving means and secondary circuits for setting up controls of varyingrestrictiveness, a decoder for governing the secondary circuits and operated by the receiving means. said decoder being arranged to distinguish between cyclic codes differing from each other by they number of separate current impulses per cycle of code, and including means making it incapable of setting up a favorable control in response to code having spaced alternate on and off periods of current, unless there intermittently occurs a relatively extended off period, and out-of-order indicating means initiated upon said decoder failing to guard against responding favorably to a code having no intermittently occurring relatively extended 'off period. I

5. In kcontinuous train control systems1n combination with code receiving means and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and operated by the receiving means, said decoder-'having means making it incapable of sett-ing upa favorable controlin response to code having spaced alternate on and off periods of current, unless there intermittently occurs an olf period which is long. relatively to said alternate off` periods, and a brake applying device controlled by said secondary circuits and operating when initiatedto apply the brakes, said decoder responding to a stop code ofsuffcient rapidity and having no EMU said intermittently occurring -extended off periods to initiate said brake applying device.

6. In continuous train control systems, in combination With code receivingineans and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and'operated by the receiving means, said decoder heilig arranged to distinguish between cyclic codes differing from each other by the number of separate current impulses per cycle of code, and including means making it incapable of setting up a favorable control in response to code having spaced alternatel on and off periods of current, unless there intermittently occurs an-oif period Which Vis long relatively to said alternate off periods, and a brake applyingL device controlled by said secondary'circuits and operating when initiated, to apply thebrakes. said decoder responding to a stop code of suicient rapidity and having no said intermittently occurring extended off periods to `initiate said brake applying device. v Y

l L7. In continuous train control systems, in combination' with code receiving means and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and operated bythe receiving means, said decoder having means making is lincapable of setting up a favorable control in response to code having spaced alternateon and off periods of currnent, unless there intermittently occurs a relatively extended off period, an out-oforder indicating means initiated upon said decoderfailing to guard against responding favorably to a code having no intermittently occurring relatively extended oft period, and a brake applying device controlled by said lsecondary circuits and operating, When initiated, to apply the brakes, said decoder responding to a stop code of sutiicient rapidity and having no said intermittently occurring extended off periods to initiate said brake applying devce.

8. In continuous train control systems, in combination with code receiving means and secondary circuits for setting up controls of varying restrictiveness, a decoder for governing the secondary circuits and operated by the receiving means, said decoder having means making it incapableY of setting up a favorable control in response to code having spaced alternate on and off periods of current,unless there intermittently occurs a relatively extended off period, a brake applying device controlled by said secondarycircuits and operating, when initiated, to apply the brakes, said decoder responding to a stop7 code of suiiicient rapidity and having no said intermittently occurring extended off periods, to initiate said brakeapplying device, means for initiating the brake applying device on going into more restrictive territory, and an acknowledging contactor incapable of preventing initiation of the brake applying device due to said fstop code, but operable to prevent the other said initiation thereof.

9. A train control decoder, comprising, a plurality of' stepping relays for selectively energizing different control circuits and operable in response to a primary relay connected tol successively pick up and release to thus follow a code, the stepping relays picking up in succession as the primary relay operates, each stepping relay picking up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, and all, save the irst, being stuck up through a circuit includinga front point of each preceding relay and a back point ofthe immediately succeeding relay, said first stepping relay controlling all said control circuits, and a monitor relay picked up through a back point of each of said stepping relays and stuck up, in multiple, through a back point of the primary relay, and a front point of the first stepping relay.

l0. A train control decoder, comprising, a `plurality of stepping relays yfor selectively energizing dilierent control circuits and operable in response to a primary relay connected to successively pick up and release to thus follow a code, the stepping relays picking up in succession as the primary relay operates, each stepping relay picking up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, and all, save the first, being stuck up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, said first stepping relay controlling all said control circuits, and a monitor relay, picked upthrough a back point of each of said stepping relays and stuck up, in multiple, through a back point ofthe primary relay and a front point of the first stepping relay, said monitor relay also controlling all said control circuits.

l1. A train control decoder, comprising a plurality of stepping relays, for selectively energizing different control circuits and operable in response to a primary relay connected to successively pick up and release to thus follov7 a code, the stepping relays picking up in successiion as the primary relay operates, each stepping relay picking up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, and all, save the first, being stuck up through a circuit including a front point of each preceding rel ay and back point of the immediately succeeding relay, said stepping relay controlling all said control circuits, and a monitor relay, picked up through a back point of each of lll said stepping relays, and stuck up, in multiple, through a back point of the primary relay and a front point of the first stepping relay, said monitor relay also controlling all said control circuits, and the stick circuits for the stepping relays, through its front points.

l2. A train control decoder, comprising, a plurality of stepping relays for selectively energizing diii'erent control circuits and operable in response to a primary relay connected to successively pick up and release to thus follow a code, the stepping relays picking up in succession as the primary relay operates, each stepping relay picking up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, and all, save the first, being stuck up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, said irst stepping relay controlling all said control circuits, and a monitor relay, picked up through a back point of each of said stepping relays, and stuck up, in multiple, through a back point of the primary relay, and a front point of the iirst stepping relay, said monitor relay also controlling all said control circuits and being quick enough acting to release if the primary relay picks up when the iirst stepping relay is down.

13. A train control decoder, comprising, a plurality of stepping relays for selectively energizing diiierent control circuits and operable in response to a primary relay connected to pick up and release to thus follow a code, the stepping relays picking up in succession as the primary relay operates, each stepping relay picking up through a circuit including a front point oli' each preceding relay and a back point of the immediately suc cee-ning relay, and all, save the first, being stuck up through a circuit including a front point oi' each preceding relay and back point or' the immediately succeeding relay, said lirst stepping relay controlling all said control circuits, and a monitor relay, picked up through a back point of each of said stepping relays, and stuck up, in multiple, through a back point oi the primary relay and a front point of the first stepping relay, said monitor relay also controlling all said control circuits and the stick circuits for the stepping relays, through its front points, the monitor relay being quick enough acting to release ir the primary relay picks up when the first stepping relay is down.

11i. A train control decoder, comprising, a plurality of stepping relays for selectively energizing different control circuits and operable in response to' a primary relay connected to pick up and release to thus follow a code, the stepping` relays picking up in succession as the primary relay operates, each stepping relay picking up through a circuit including a front point of each preceding relay and a back point of the immediately succeeding relay, and all, save the first, being stuck up through a circuit including a front point of each preceding relay and back point of the immediately succeeding relay, said first stepping relay controlling all said control circuits, and a monitor relay, picked up through a back point oi' each of said stepping relays and stuck up, in multiple, through a back point oi' the primary relay and a front point of the first stepping relay, said monitor relay also controlling all said control circuits and the stick circuits for the stepping relays through its front points, the monitor relay being quick enough acting to release if the primary relay picks up when the iirst stepping relay is down, and an out-of-order indication connected to be energized if the monitor relay fails to release when de-energized. A

15. A decoder for train control systems, consisting, of only a plurality of stepping relays picked up in succession as a primary relay, arranged to Jfollow train control code, picks up and releases, each stepping relay, eX- cept the last, picking up through a back point or a following relay, and each stepping relay, except the lirst, picking up through a front point of a preceding relay.

i6. A decoder for train control systems, comprising a plurality of stepping relays picked up in succession as a primary relay, arranged to follow train control code, picks up and releases, each stepping relay, except the last, picking up through a back point of a following relay, and each stepping relay, eX- cept the iirst, picking up through a front point of a preceding relay, a stick circuit `for the irst stepping relay including a front point of the primary relay, a stick circuit for the other stepping relays including a front point of the first stepping relay, anda plurality of induction control circuits energizable through a back point of the first stepping relay.

i7. A decoder Jfor train control systems, comprising, a plurality of stepping relays picked up in succession as aprimary relay, arranged to follow train control code, picks up and releases, each stepping relay, except the last, picking up through a back point of following relay, and each stepping relay, except the first picking up through a front point oic a preceding relay, a stick circuit for the first stepping relay including a front point of the primary relay, and front and back points of succeeding relays, a stick circuit for the other stepping relays including a front point of the first stepping relay, and a plurality of indication control circuits energizable through a back point of the iirst stepping relay.

In testimony whereof I affix my signature.

, WILLIAM D. Hannes. 

